1. Technical Field
The present invention relates to an image file creation device, method and program storage medium, an image processing device, method and program storage medium, and an image processing system that handle image files by taking color appearance into consideration.
2. Related Art
When acquiring multicolor image data or an image itself by an input device, or displaying or print-outputting by an output device, the color reproduction regions are determined in accordance with the characteristics of tile respective devices. For example, in a case of outputting an image from an image forming device, when a color that cannot be reproduced at the image forming device is included in the image for which outputting is instructed, conversion processing (color region compression processing or color correction processing) for keeping the color within the reproducible color range will be carried out. At a device such as an image forming device, an image is formed by using color materials, and the colors of the image are expressed in a device color space whose essential elements are the colors of these color materials. The CMYK color space and the like are known as examples of device color spaces. Further, in conversion processing relating to color, it is preferable to carry out processing in a color space that does not depend on characteristics of individual devices (a device-independent color space). The CIELAB color space, the CIEXYZ color space and the like are known as examples of device-independent color spaces.
A color management system (CMS) is known in order to manage colors between devices that differ in this way. The CMS can manage calorimetric colors even between different devices, by exchanging color information between the devices via a color space that does not depend on a device, such as the CIEXYZ color space or the CIELAB color space.
A color image is dependent on the surrounding environment in which that color image is viewed. Therefore, there are cases in which color appearance differs in accordance with the viewing environment. Thus, in order to address the variations in color appearance due to the viewing environment, there have been proposed systems in which the concept of a color appearance model (CAM) is introduced into the CMS, and differences in appearance due to viewing environments are taken into consideration. Data of the viewing environment is needed in such a system.
However, providing sensors in order to take the appearance of a color image into consideration is expensive. Further, periodic calibration is required in order to maintain the accuracy of the sensors, and management will be complex. Note that, because the appearance of a color image depends on the viewing environment, there are cases in which the measured values fluctuate greatly. Namely, even in the same environment, there are cases in which the measured values differ greatly due to the effects of external light, the colors and arrangement of peripheral objects, the positional relationship between the measuring and illuminating devices, and the like.
Further, it has been thought to take the appearance of a color image into consideration by preparing in advance correction values that correspond to the conditions of a viewing environment and to set these to reproduction devices, without using sensors. However, in such a case, extensive knowledge regarding the appearances of color images, such as that of an experienced person or the like is required, and there is a strong possibility that inappropriate settings may be carried out.
Moreover, in the printing industry field, there are cases in which color management which carries out colorimetric matching for plural color images is demanded. In a CMS in which a CAM is introduced such as described above, colorimetric matching cannot be realized if the viewing conditions are not set appropriately.